Hydrodynamic universal joint



1952 E. L. RUBERTS ETAL HYDRODYNAMIC UNIVERSAL JOINT Filed Nov. 29. 1946 INVENTORS Ma /M; 1?:4fi6/ Zs wad/WA Patented Aug. 5, 1952 nrnnonrNsMlc UNIVERSAL Jomr z Edwin L. Ruberts and Edwin M. Rubens} tf 'tawa, 111.; said Edwin M. Ruberts assignor to saidEdwinLRuberts The present invention relates in general to hydro-dynamic; couplings and; in particular, to an improved form of universaljoint wherein power is transmitted between driving and driven shafts through a fiuidtransmission medium.

vOneapplication forwhich the universal joint of the present invention is particularly suited is the transmission of power to the wheels of an automobile employing afront wheel drive, The mechanically coupled type of universal joints heretofore'employed for this purpose are short lived, due to the severeoperating conditions to which they are subjected in such service.

Itisian object of the present invention to pro,- vide aruniversaljoint which is extremely rugged and durable and is well adapted to :transmit power between misaligned shafts under severe operating conditions such as that encountered afront wheel drive automobile.

A further object of theinvention is to provide an improved form :of universal joint wherein friction between the driving and driven members caused by misalignment of the driving and driven shafts issreducedrto a minimum, .whereby'a high transmission efficiency is obtained. 1

Another objectrof the inventionjs'to provide a universal joint which is encased by intermeshing relatively. stationary spherical shells which serve to protect the rotating mechanism from in-, jury, and to guard against unintentional contact therewith. 1 i g A still further object of the invention is to pro-. videva universal joint which is constructed in such manneri as to avoidvthe creation of undue stresses wtherein when the driving and driven shafts ,are'notin alignment, whereby theistruce tural elements may be made relatively light .and are also subjected to less wear than occurs in conventional types of universal joints. j t

Still another object of the invention is tov provide an improved form of universal joint wherein the driving and driven shafts each rotate at a uniform velocity despite misalignment thereof, rather than oscillating about, a mean velocity as occurs in most of the universal joints heretofore known.

These and other objects of the invention will be more fully understood upon a perusal of the following specification taken in coniunctionwith the accompanying drawing, wherein:

Fig. 1 is a perspective view of a universal joint constructed, in accordance with the invention, withthe driving and driven shafts shown out of alignment 1 2,515,

str ss ng sealants View tries .JApplication vbvember 29, 1946', serial Nd. 713,176, J i .Tncnmi. (Otto-54) universal joint shown in Fig. l, with 'the driving and driven shafts shown in alignment; and

Fig. 3 is a transverse sectional view of the universaljoint, taken alongthe uses-s ofFlg; 2. Described briefly, the'universal joint,.'or fluid coupling, of the present invention comprises a pair of concentric spherical shells forming, a fluid-tight chamber within which there is disposed an impeller and a runner, which are likewise .constructed in the form of concentric spherical shells. A driving shaft is journaled in one of the outer shells and is coupled to one of the inner shells, or the impeller. A driven shaft is journaled in the. other outer. shell and is coupled to the other inner shell, or the runner, The

impeller shell is. provided with a series of arcuate vanes spaced about the periphery thereof and lying inplanes which include theaxis of rotation of the driving shaft. The runner shell is provided with a plurality of arcuate grooves spaced about the periphery thereof and lying in planes which include the axis of rotation of the driven shaft. When the driving shaft is' rotated, the impeller vanes force the transmission fluid through openings in, the impeller shell against the runner shell to effect rotation thereof in the manner of aturbine. 7 Y. I

, Referring now particularly to Fig. 2 of the drawing, there is shown a pair of concentric spherical shells 4 and 5, each of which is constructed in two parts, 4w4b and Ba-Bb, to facilitate assembly thereof. The outermost shell 4 has a hub- 8 extending therefrom which is riveted to a housing It encasing a driven shaft I2. The shaft [2 isjournaled in the hub 8 by a ball bearing unit lfll, which is secured in place by an annular ring I6 threaded into the hub 8.

In like manner, the shell 6 is provided with a hub 18 whichis riveted to a housing 20 encasin a driving shaft 22. The driving shaft 22 is journaled in the hub l 8.by means of a ball bearing unit 24, which is securedin place by an annular ring 26 threaded into the hub l8. Oil seals 28 and 30 are provided-t1; prevent escape of oil from the fluid chamber formed by shells 4 and 6 into the space between the driving or driven shaft housings and the shaftswhich they encase.

A sealing ring 32, which isretained in an annular recess in the spherical shell 4, is provided. to prevent leakage of oil from the fluid chamber through the space between the shells 4 and 6. It is to be understood that oil is allowed to penetrate the space between shells 4 and, 6 up to the sealing ring, 32 to serve as a lubricant which promotes. sliding of one ofrthese shells after passing through clearance holes in a hub 1-6 formed on an impeller shell 48. l

A series of impeller vanes orblades iil are secured to the inner wall of jtheimpeller shell 48 by means of machine screws 52, which pass through counter-bored openings in the shell 48 into tapped openings in hanga s! formed ontheimpeller blades. On each side of the impeller blades 50 there extend-rows of circular openings es and 5c in the, impeller 511611.48. rn openins lit on one side *of 'eacii ofthe impeller may best "be-seen in iFig. v V to" is ;provided with; a 'series' of arcuate, grooves 62 extending froman open;portion of the shell to av point near the hub} 38 thereof. The space betweenthe impelle v Sh ll 48 an'd the runner shell 48 s ad re r malt s y in h -Or e O 5 ch to".-Q 5: rshi iqn't s ze t joint and the particular application in which it is employed .4 W I The ;transversE crossZ section [of the theater blades 5B "is f concave, whereby they form scoops which force the fluid transmission mediumoutwardly through adjacent openings 56 or 52, de- 7 pending on the direction of rotation of the impeller shell. Assuming that the impeller shell 33 is rotatingjclockwise, as viewed; in Fig. 3, the

im eia bl e 0 il i f e t id ed u outwardly through the openings je adjacent thereto, which openings are skewed so as't'o cause the ifluid issuing therefrom to impinge on therum ner shell 4D "at,v a higher velocityf than the suriaceivel-ocity of the impellershell' 4B. As the iluidmjedium ejected; through the openings 58 impinges on the sidewalls of the grooves 62in the runner shell :40 a portion ofthe kinetic energy of the fluid is transferredto the runner shell causingit to rotate in'a clockwise direction as viewed in'FigL '3. If 'IthB impeller shell 4 8"is r0- tated in the opposite direction, the fluid transmission medium is forced outwardly through the openings 56 'to impinge on the opposite side walls of the grooves 62 in the runner shelllfl, causing it to rotateinthereverse-direction.

Thefluid'chamb'er, formed by shells 4 and 6 is filled with transmission fluid{ through an opening -64 in the -outermost shell 4,}which opening is normally sealed by a pl'ug- "iiiijthreaded therein,- The fluid whieh is el'fij fi ed' from the impeller shell i'8 andj impiii'ges 'on the runner shell 40 flows along-- the groov s therem toward'the hub 38, or toward the opening on the OppQs'it'e Side of the shell, andjthence" flowsthrough' the" opening in the impeller shell opposite theihub'flif thereof, or through the openings GO spaced around the hub' 46. I 2,

rush-cum be apparentthfatg byreason or-the sphericai eonfiguranon (if-the nnpener' ana the germane shell runner elements of the universal joint, power will be transmitted from one element to the other despite misalignment of the driving and driven shafts. It should also be apparent that, due to the symmetrical relation of the driving and driven elements for any position thereof with a fixed angle, between the axes ofthe shafts the driven shaft will rotate at a uniform velocity, assuming that the driving shaft rotates at a uniform velocity. The speeds of the two shafts will usually be different however. As there is no mechanical contact between the driving and driven members,

there. is very little frictional loss created by the which occurs when the shafts l2 and 22 are not in alignment.

.It is to be'understood that the impeller and runner elements may consist of driving and driven vanes which are self-supporting and are disposed in concentric-spherical surfaces, instead of attaching impeller vanes to one spherical shell and forming runner vanes in a second spherical shell by milling grooves in the surface thereof. It should also be understood that the impeller shell may have blades of suitable construction placed on its outside surface rather than on its inside surface, and thus may be disposed on the outside of the runner shell which then must have grooves in the outer rather than the inner surface.

Since the stresses in the rotating elements areno greater when the driving and driven shafts are out of alignment than they are when these shafts are aligned, the parts need only be constructed strong enough to withstand the stresses which occur when power is being transmitted between aligned shafts. Therefore, a lightweight and compact universal joint, constructed in accordance, with the principles of the present invention, is capable of transmitting considerable power since the cushioning effect of the ;oil avoids the creation of any undue stresses therein. At the same time the power 7 loss due to friction is reduced when the driving and driven shafts are out of alignment, as compared with conventional universal joints, since the frictional forces are usually much greater in conventionaluniversal joints when the shafts are out of line;

When the lubricating oil used with a conventional universal joint runs low, rapid wearing occurs and can oftentimes go unnoticed until the joint has been badly scored or otherwise damaged. The present universal joint is practic'ally self protecting in that a loss of oil immediatelyevidences itself by reason of the fact that- 'the efficiency of power transmission is greatly-reduced; and, in the extreme case of complete loss of oil, power transmission may fail completely. 7 While a particular embodiment of the invention has been disclosed by way of illustration,

may be relatively varied, and a hydro-dynamic coupling for joining said shafts and including a set of impeller blades fixed on said driving shaft and a set of cooperating turbine blades fixed on said driven shaft, said impeller and turbine blades being operative to transmit power from the driving shaft to the driven shaft for either direction of rotation of the driving shaft to cause the driven shaft to rotate in like direction, and each set of blades being of substantially truncated spherical form and relatively positioned one Within the other to afford a coupled driving connection therebetween, and means maintaining the relative position of the sets of blades one within the other while providing for substantially universal relative shifting therebetween whereby rotation of the driving and driven shafts may be effected with their axes of rotation out of alignment.

3. In combination, a driving shaft, a driven shaft, the angular relation between the axes of rotation of said shafts being variable, and a hydro-dynamic universal joint including mechanical parts universally coupled by a fiuid medium coupling said shafts, said universal joint coupling including ball and socket members, said members being fixed on said driving shaft and on said driven shaft, impeller blades on one of said members, and cooperating turbine blades on the other of said members, said universal joint being operative to transmit power to the driven shaft from the driving shaft for either direction of rotation of the driving shaft to cause the driven shaft to rotate in a like direction.

4. A hydro-dynamic coupling comprising an impeller having a plurality of impeller blades, a runner having a plurality of turbine blades, a casing filled with a fluid transmission medium and enclosing said impeller and said runner, a driving shaft fixed to said impeller and sealed in fluid-tight relation to said casing, a driven shaft fixed to said runner and sealed in fluidtight relation to said casing, and said casing including spherical shells concentrically movable in any direction with respect to each other whereby to permit relative angular disposition of the axes of the coupled driving and driven shafts.

5. A universal joint comprising an impeller, a runner, said impeller and runner being constructed in the form of nested and interconnected truncated spheres of different diameters carrying opposed impeller and runner blades and being disposed in concentric relation, said impeller and runner being shiftable substantially universally relative to one another, and a casing filled with a fluid transmission medium and enclosing said impeller and runner.

6. A universal joint comprising a pair of concentric spherical shells forming a fluid-tight casing, said shells being concentrically movable in any direction with respect to each other, a driving shaft sealed in fluid-tight relation to one of said. shells, a driven shaft sealed in fluid-tight relation to the other of said shells, an impeller secured to said driving shaft and disposed within said casing, a runner secured to said driven shaft and disposed within said casing in close proximity to said impeller, and a fluid transmission medium in said casing.

7. A universal joint comprising a pair of concentric spherical shells forming a fluid-tight casing, said shells being concentrically movable in any direction with respect to each other, a driving shaft sealed in fluid-tight relation to one of said shells, a driven shaft, sealed in fluid-tight relation to the other of said shells, a spherically shaped impeller secured to said driving shaft and concentrically disposed within said casing, a spherically shaped runner secured to said driven shaft and concentrically disposed within said casing in close proximity to said impeller, and a fiuid transmission medium in said casing.

8. Power transmission device comprising coupling parts capable of substantially universal angular movement relative to each other, and hydraulic drive means formed in said coupling parts for rotating one part from rotation of the other, said drive means including impeller blades and turbine blades on said parts respectively shaped to afford angular movement of one part relative to the other.

9. A power transmission device as set forth in claim 8 wherein the coupling parts comprise ball and socket members.

10. A power transmission device as set forth in claim 8 wherein the coupling parts comprise substantially truncated spheres concentrically disposed.

11. A power transmission device comprising a universal coupling having a substantially spherical ball-like part fitting within a shell part, and interconnected for permissive relative angular disposition between the axes thereof, impeller vanes rigid with said spherical coupling part and arranged concentrically, blade means rigid with the shell coupling part and in opposed relation with said impeller vanes, and liquid within the coupling parts so that rotative movement of one part through the vanes and blades imparts corresponding movement to the other part in any one of a number of relative angular positions thereof.

EDWIN L. RUBERTS. EDWIN M. RUBERTS.

' REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,078,710 Weir Nov. 18, 1913 1,291,871 Hein Jan. 21, 1919 1,428,586 Garrison Sept. 12, 1922 1,583,736 Nydqvist May 4, 1926 1,667,565 Radcliffe Apr. 24, 1928 1,885,746 Martin Nov. 1, 1932 2,182,049 Henry Dec. 5, 1939 2,401,376 Sherman June 4, 1946 FOREIGN PATENTS Number Country Date 67,202 Sweden Apr. 16, 1929 

